Open AccessNighttime radiative cooling in hot and humid climates
Author(s) -
Minghao Dong,
Nan Chen,
Xiaodong Zhao,
Shanhui Fan,
Zhen Chen
Publication year - 2019
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.27.031587
Subject(s) - radiative cooling , relative humidity , radiative transfer , atmospheric sciences , environmental science , humidity , radiant cooling , materials science , meteorology , radiant flux , optics , physics
Most existing experiments on radiative cooling are conducted in dry climates for better performance. However, many important applications require cooling in hot and humid climates. Here we theoretically analyze the temperature reduction and cooling flux at nighttime with the ambient temperature (Tambient) ranging from 0-40 ∘ C and the relative humidity (RH) from 0-100%. Our analysis reveals an interesting crossover: for lower (higher) RH, higher (lower) Tambient results in better cooling. Experimentally, we show that radiative cooling of 5 ∘ C below ambient can be achieved even at Tambient = 29 ∘ C with RH = 100%.